Let's start by stipulating that there are many types of photographers and styles of shooting. Now with that out of the way we can make it clear that these new iPhone apps, avaialable in the app store  Viewfinder Standard andViewfinder Pro are intended for those of us who sometimes work slowly and deliberately, deciding on a framing and composition for a shot even prior to opening up our equipment bag.

If you are among those who work this way (at least some of the time) you may well already walk around with some sort of framing device. This can be as simple as a piece of shirt stiffening cardboard with a rectangle cut from it, to an accessory viewfinder such as the lovely but oh-so expensive Linhof zoom finder.

Another alternative is the directors viewfinder, used by cinematographers and videographers, though these aren't quite suitable for still photographers because they don't include the focal lengths and aspect ratios which we use.

But now there...